Ventricular Assist Device
A ventricular assist device (VAD) is a mechanical pump used for blood circulation support. It decreases the workload of the heart while maintaining adequate flow and blood pressure.
Purpose
A VAD is a life-sustaining device. VADs can support the left ventricle (LVAD), the right ventricle (RVAD), or both ventricles (BIVAD). They are used when the heart muscle is damaged and when blood flow from the heart is inadequate. VADs are implanted either as a bridge in patients awaiting heart transplantation, in patients who have rejected a transplanted heart, or as a permanent device for those patients with severe cardiac dysfunction but who are not eligible for a heart transplant.
Examples of patients who might be candidates for a VAD are those who:
- have suffered a massive heart attack
- cannot be weaned from heart-lung bypass after treatment with intravenous fluids, medications, and insertion of a balloon pump in the aorta
- have an infection in the heart wall that does not respond to conventional treatment
- are awaiting a heart transplant and are unresponsive to drug therapy and intravenous fluids
Although one in five people suffer left side ventricular failure, only a minority are candidates for VADs. To be considered for a VAD, patients must meet specific criteria concerning blood flow, blood pressure and general health.
Precautions
Poor candidates for a VAD include those with:
- severe disease of the vascular system of the brain
- cancer that has spread (metastasized)
- severe liver disease
- blood clotting disorders
- severe lung disease
- infections that do not respond to antibiotics
- extreme youth or age
Description
There are various types of VADs, each appropriate for a different condition. Surgery to implant a VAD is performed under general anesthesia in a hospital operating room. An incision is made in the chest, and then catheters are inserted into the heart and the correct artery. The surgeon sutures the catheters in place, and then attaches tubing to connect the catheters to the pump. Once it is turned on, blood flows out of the diseased ventricle and into the pump, and then is returned to the correct blood vessel leaving the heart.
Preparation
Before the operation the patient meets with an anesthesiologist to determine any special conditions that will affect the administration of anesthesia. Standard preoperative blood and urine studies are performed, and the heart is monitored both before and during the operation.
A full explanation, both written and verbally regarding risks, benefits and after care are given to both the patient and their support system. Extensive consent forms are reviewed and signed as well.
Aftercare
The patient is monitored in intensive care, with follow-up blood, urine, and neurological studies. Blood thinning medications are given to prevent blood clotting. Due to clinical status prior to the implant, many patients require in-patient intensive rehabilitation. Total lengths of stay at both St.Vincent and the rehabilitation centers vary from 14 days to 3 months, again, depending on the patient’s clinical status prior to the implantation, as well as post-implant.
Following the immediate post-operative period, intense patient and support persons (spouse, sibling, significant other) education is initiated. Both the patient and their support persons must have the ability to complete all aspects of VAD care, from dressing change to mechanical correction.
Once discharged, the patient will be seen on a routine basis in the VAD clinic, as well as continued cardiac rehab outpatient sessions to improve strength and ability to regain a normal lifestyle. Those patients awaiting a transplant must follow this same regimen, as this results in much better outcomes following transplantation.